为了研究连续液滴对固壁面的撞击影响, 引入一种纯Lagrange、无网格计算方法, 即光滑粒子流体动力学方法(SPH)。对连续液滴撞击固壁面的扩散、回弹及飞溅进行了数值模拟并与实验测试进行比对。结果表明:连续液滴撞击固壁面时, 液滴的自由表面变化具有许多不确定性, 其中次生液滴的产生和韦伯数的作用是影响液滴撞击扩散的主因。次生液滴的出现使得液滴扩散及飞溅变得更为明显, 韦伯数越大, 连续液滴的无量纲直径变化越快。模拟效果真实反映了液滴撞击过程, 可为类似撞击问题的仿真分析提供借鉴。
In order to study the continuous droplet impinging on solid surface, a pure Lagrange and meshless method, namely the smoothed particle hydrodynamics (SPH) method is used. The spreading, rebounding and splashing processes of the continuous droplet impinging on solid surface are simulated with the SPH, and the results are compared with experiments. It is shown that in the continuous droplets impinging on solid surface, there are many uncertainties with respect to the free surface of droplets. The effects of the secondary droplets and the Weber numbers might be the main factors that influence the impinging diffusion of droplets. The secondary droplets help the droplet spreading and splashing. With the increase of the Weber number, the dimensionless diameters of continuous droplets change faster. The simulation results truly reflect the impact process of droplets, to provide a reference for simulation analysis of similar impinging problem.
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